Process for hydroconversion of organic materials

ABSTRACT

A process for hydroconversion or organic materials, particularly solid or very high boiling organic materials, by contacting such materials under hydrogen pressure and at elevated temperature with a continuous liquid phase catalyst containing gallium trichloride, gallium tribromide, gallium triiodide, mercuric bromide, mercuric iodide, stannic bromide, stannic iodide, stannous chloride, stannous bromide, stannous iodide, zirconium tetrachloride, zirconium tetrabromide, zirconium tetraiodide, titanium tetrabromide, titanium tetraiodide, titanium triiodide, cuprous chloride, cuprous bromide, cuprous iodide, hafnium tetrachloride, hafnium tetrabromide, or hafnium tetraiodide.

United States Patent Kiovsky et al.

[ June 6,1972

[54] PROCESS FOR HYDROCONVERSION OF ORGANIC MATERIALS [72] Inventors: Thomas E. Kiovsky, El Sobrante; Milton M. Wald, Walnut Creek, both of Calif.

[73] Assignee: Shell Oil Company, New York, NY.

[22] Filed: Aug. 31, 1970 [21] Appl. No.: 68,203

[52] U.S. CI ..208/10, 208/108 I51] Int. Cl. C101; l/06, Cl0g 13/02 [51%| Field 01 Search .208/10, 108

[56] References Cited UNITED STATES PATENTS 2,221,952 11/1940 Pier et al ..208/108 2,191,156 2/1940 Pier et a1 ..208/108 1,938,542 12/1933 Pier et al ..208/10 RE ACTOR Primary Examiner-Delbert E. Gantz Assistant ExaminerVeronica OKeefe Attorney-Glen R. Grunewald and John H. Colvin [57] ABSTRACT A process for hydroconversion or organic materials, particularly solid or very high boiling organic materials, by contacting such materials under hydrogen pressure and at elevated temperature with a continuous liquid phase catalyst containing gallium trichloride, gallium tribromide, gallium triiodide, mercuric bromide, mercuric iodide, stannic bromide, stannic iodide, stannous chloride, stannous bromide, stannous iodide, zirconium tetrachloride, zirconium tetrabromide, zirconium tetraiodide, titanium tetrabromide, titanium tetraiodide, titanium triiodide, cuprous chloride, cuprous bromide, cuprous iodide, hafnium tetrachloride, hafnium tetrabromide, or hafnium tetraiodide 5 Claims, 1 Drawing Figure SEPARATOR FRACTIONATOR lo REGENERATOR EXTRACTOR PATENTEDJUH 5 m2 3,668,109

II E L} Q z E 9 r X l- Lu 0 I!) i, 0: LL

SEPARATOR FLASHER REGENERATOR REACTOR INVENTOR Z THOMAS E. KIOVSKY MILTON M. WALD ATTORNEY PROCESS FOR HYDROCONVERSION OF ORGANIC MATERIALS BACKGROUND 1 now more desirable than ever to convert these materials into lower boiling liquids, particularly clean-buming lower boiling liquids that can be employed as fuel for furnaces, internal combustion engines or turbines without causing atmosphere pollution by producing sulfur oxides.

Conversion of materials such as coal and residual fractions of petroleum is difficult. Thermal conversion produces large volumes of undesirable products such as normally gaseous hydrocarbons and condensation products such as coke, and much of the sulfur from the feed remains in the products. Catalytic processes for conversion, which result in more useful products, are generally not economic with coal and residual petroleum fractions because they contain so many materials that poison catalysts. Coal contains mineral ash which clogs heterogeneous catalyst beds, and heteroatomic molecules containing oxygen, sulfur, nitrogen, etc., which react with hydrogen to produce water, hydrogen sulfide or ammonia which are frequently detrimental to catalysts. Additionally, coal consists largely of condensed ring aromatic hydrocarbons which are difiicult to convert and are subject to coking.

Residual petroleum fractions also contain difficult material to convert such as asphaltenes and condensed ring aromatic molecules as well as impurities such as organically bound nickel and vanadium which are detrimental to catalysts.

THE INVENTION The present invention involves a process for converting difficultly converted organic materials to valuable liquid products by contacting those materials with a catalytic continuous liquid phase including gallium trichloride, gallium tribromide, gallium triiodide, mercuric bromide, mercuric iodide, stannic bromide, stannic iodide, stannous chloride, stannous bromide, stannous iodide, zirconium tetrachloride, zirconium tetrabromide, zirconium tetraiodide, titanium tetrabromide, titanium tetraiodide, titanium triiodide, cuprous chloride, cuprous bromide, cuprous iodide, hafnium tetrachloride, hafnium tetrabromide or hafnium tetraiodide under hydrogen pressure of at least 250 psi and at a temperature of from 200 c.-550 C. The continuous liquid phase catalyst may be the molten catalytic material per se, mixtures of molten catalytic salts or molten catalytic salts mixed with melting point-depressing materials such as alkali metal salts or solvents for the catalytic material.

The organic material capable of conversion by the process of this invention includes but is not limited to coal, lignite, oil bearing shale and other carbonaceous solids as well as petroleurn derived liquids, tar from tar sand extract and other liquids.

The high activity of the catalysts of this invention permits conversion of the charge at temperatures low enough to favor the production of large amounts of valuable liquid hydrocarbons such as gasoline and turbine fuel without the production of large amounts of propane and lighter material or of coke. Moreover, the gasoline boiling range material in the product contains high proportions of highly branched paraffins and of cycloparaflins which are respectively high octane components and excellent reformer feedstocks to produce high octane gasoline. Even though the catalysts employed in the present invention are active catalysts, they are not readily poisoned in that they are present in large quantities and their catalytic activity is not dependent on surfaces subject to attack by catalyst poisons, coke, metallic residues and mineral matter.

The process of this invention involves contacting the charge with the above-mentioned liquid phase catalyst system at a temperature of from 200' to 550 C., preferably from 275 to 450 C., at which temperature the reaction rate is adequate to effect the process quickly without the production of too much propane and lighter material and at a temperature where hydrogenation is favored. The reaction must be effected under hydrogen pressure of at least 250 psi, preferably at least 800 psi, and generally at pressures in excess of 1,000 psi. Pressures in excess of 2,000 psi, at the temperature conditions and with the active catalysts employed herein, rarely produce advantages and need not be employed, which is a significant advantage of the process of this invention. Different catalysts and difierent feeds require different conditions, but in general lower temperatures and higher hydrogen partial pressures result in a more saturated product while higher temperatures result in a product with a lower average molecular weight.

The process of this invention may be operated either in batch or continuous manner and preferably is operated continuously for the usual reasons of high production, high efficiency, and continuous product characteristics.

When the process is operated continuously and coal or other solid phase feed is employed, the feed may be introduced into the reaction zone either finely ground and suspended as a pumpable slurry, extruded therein as a dry solid, or introduced intermittently through lock chamber devices. If the charge is fed dry it need not be finely ground in that the particles disintegrate rapidly in the continuous phase catalyst. Since some liquid phase catalysts escape with the product and must be separated therefrom, the liquid phase employed for slurrying solids advantageously is recycled catalyst; however, a fresh liquid feed or high-boiling recycled portion of the product may be employed as a slurry liquid.

Hydrogen is preferably introduced beneath the surface of the continuous phase catalyst so that it is absorbed in the.

catalyst and available to hydrogenate the feed prior to or simultaneously with the cracking reactions that are effected. The hydrogen may be from any source and need not be pure. For example, hydrogen resulting from a reforming process that contains light hydrocarbons, hydrogen sulfide, carbon monoxide, or water may be employed. The hydrogen preferably is introduced either mingled with the feed or at least beneath the surface of the continuous catalyst phase in the form of finely dispersed bubbles, and hydrogen is preferably separated from other vapor phase products of the conversion and recycled to the reaction vessel. The manner of introducing hydrogen may stir the system, and additional stirring may be provided if required.

Although the catalyst of the present invention is very durable and resistant to poisoning, in a continuous process some catalyst treatment will be required. Most of the catalysts of this invention are substantially completely resistant to water and hydrogen sulfide, but ammonia produced by hydrogenating nitrogen containing molecules will react with the metal halide catalyst to produce an ammonium halide-metal halide complex or ammine complexes that do not have the desired cracking activity. Solid ash from coal, unconvertable hydrocarbons generally referred to as char, metal impurities, and other solid materials may accumulate in the continuous phase catalyst and materials of this nature must be removed from the catalyst. The undesired materials removed from the catalyst may be treated to recover or regenerate metal halide catalyst by thermally or chemically breaking down the complexes or by oxidizing metal that was reduced from the metal halide and returning the restored metal halide to the reaction zone. The solid impurities may be removed by filtration,-extraction or other means, and disposed of.

The metal halide catalysts employed in this invention are surprisingly active and durable and they promote both cracking reactions, as evidenced by the low boiling range of the product as compared with the character of the charge, and hydrogenation reactions as evidenced by hydrogen consumption during processing and the saturated nature of the product. The reactions are effected in such a manner that almost the entire charge is converted to lower boiling products that are clean, liquid phase, and quite useful in themselves or as feedstocks to subsequent processes.

The following examples are presented to illustrate various aspects of the present invention and are provided to be illustrative rather than limiting on the scope of the invention. In all of the examples shown in the table below the reactions were effected in autoclaves by introducing all of the feed and catalyst into the autoclave and maintaining contact of the various materials for periods up to 30 minutes after which the materials were removed from the autoclave and the products collected and analyzed. In some experiments all of the hydrogen was introduced into the autoclave before the reaction was begun while in others hydrogen was bubbled through thcautoclave at a fixed pressure during the course of the reaction. In all cases the starting hydrogen pressure was between 1,700 and L800 psig. The charge in all cases unless otherwise indicated was Illinois No. 6 coal ground to 200 mesh particle size. The only products reported are those boiling below 250 C., but liquid phase material boiling higher than 250 C. was also recovered. The products are measured on the basis of weight percent and are reported as grams of product per hundred grams of moistureand ash-free coal (MAF). Products are reported in this manner because it indicates the amount of conversion of material in the charge that is capable of being converted by this process, and eliminates the weight of charge represented by moisture and ash, the amounts of which are fortuitous with regard to the process and would render conversion figures less significant. In all experiments, the liquid product that was recovered, both thatboiling below 250 C. and that boiling above 250 C. contained negligible quantities of combined sulfur, oxygen, nitrogen and organo-metallic and the product is withdrawn through line 7. The product in line 7 is more highly saturated than the charge, it has a lower molecular weight than the charge, and the hydrocarbon portion of the product is substantially free of combined oxygen, nitrogen, sulfur and organo-metallic compounds.

The product passing through line 7 enters separator 8 wherein hydrogen is separated from the other products and recycled back to the reactor 4 through the beforementioned line 5. The remainder of the product is passed through line 9 into fractionator 10 wherein it is separated into various fractions. For example, water, hydrogen sulfide, ammonia and propane and lighter hydrocarbons may be removed through line 11 while gasoline and heavier products pass through line 12 for further fractionation and processing. It is evident that the material in line 7 may be treated in many ways to separate water, hydrogen sulfide, ammonia, entrained catalyst and other materials and to treat each of these appropriately.

As the reaction proceeds impurities such as reduced catalyst, ash, char, and ammonium halide-metal halide complex will accumulate in the continuous phase catalyst in reactor 4. To maintain the catalyst activity at a constant level a stream of catalyst is removed from reactor 4 through line 13 and introduced into extractor 14 where it is countercurrently contacted with a suitable solvent, preferably toluene, which extracts metal halide and hydrocarbon from the catalyst and removes them through line 16 into a flasher 17 which separates toluene from the extracted metal halide and hydrocarbon. The toluene is returned to extractor 14 via line 15 for additional contact with catalyst while metal halide and hydrocarbon pass through line 18 into reactor 4.

The unextracted material from extractor 14, which may include the above-mentioned metal halide complexes, reduced metal, ash and char passes through line 19 to regenerator 20 compounds- 3 5 wherein material capable of being regenerated to metal halide TABLE Conversion (1,700 p.s.i. H: pressure) Product, g./100 g. Catalyst MAF coal Temp Charge Weight, Run grams Identity grams C -C 04-250 C.

300 10 IlgIz 220 2. 6 31.1 325 10 HgBl'z 200 5. 0 27.5 250 10 GaBr 93 2. 5 38. 5 350 10 lnBr lPbBr 42/174 3. 8 14.4 350 20 S111: 185 3. 2 15.5 350 20 Still 150 7.1 18. 8 350 20 SnBn/IIBr 125 20 5. 7 21.0 200 20 ZrCh/KCl/NaCl 125/14/10. 5 0. 29 19.2 350 .20 S110]: 150 2.0 17.6 375 .20- sum-2 150 4.2 26.5 350 20 CuCl/CuBr/Cul 59/72/76 1. 4 10. 9 350 20 Tim, 100 5. 1 40.1 350 20 'IiIi 100 9. 4 42. 3 350 20 TH; 92 11.0 31.7

Gas oil boiling between 285 and 380 C. i The accompanying drawing illustrates schematically a flow is regenerated and returned through line 21 and line 13 to exdiagram of one process embodying this invention. The drawtractor l4, and unconvertable material such as ash and char ing is highly schematic and is intended to illustrate various are removed through line 22. The regeneration effected in functions without illustrating the valves, pumps, instruments, vessel 20 may include thermal decomposition of the comheat exchangers or other conventional means that would be plexes, chemical decomposition of the complexes and oxidaemployed to efiect those functions. tion of reduced catalyst to produce the catalytic metal halide. In the drawing the organic material charged to the process i 60 The extraction and regeneration of catalyst illustrated herein introduced through line 1 and raised to the pressure of the reactor through pump 2, which discharges into line 3 passing into a reactor 4. The material charged to the process may be any organic material capable of being converted by the catalyst, for example, petroleum, coal, tars recovered from tar sands, and shale. In reactor 4 the charge is brought into contact with a continuous phase of at least one molten metal halide catalyst useful in this invention and with hydrogen introduced into reactor 4 through line 5. The hydrogen in line 5 includes hydrogen recycled within the process as well as fresh hydrogen introduced through line 6. In a preferred embodiment reactor 4 is maintained at about 350 C. and at a hydrogen pressure of about 1,800 psi. As a result of the contact of the feed and catalyst at these conditions, hydroconversion reactions including cracking and hydrogenation occur may be accomplished by other means.

What is claimed is:

l. A process for hydroconversion of organic materials to produce lower boiling materials comprising contacting the organic materials with a continuous liquid phase catalyst consisting essentially of a metal halide selected from gallium trichloride, gallium tribromide, gallium triiodide, mercuric bromide, mercuric iodide, stannic bromide, stannic iodide, stannous chloride, stannous bromide, stannous iodide, zirconium tetrachloride, zirconium tetra-bromide, zirconium tetraiodide, titanium tetrabromide, titanium tetraiodide, titanium triiodide, cuprous chloride, cuprous bromide, cuprous iodide, hafnium tetrachloride, hafnium tetrabromide, and hafnium tetraiodide, with said continuous phase being from 200 to 550 C. and under hydrogen partial pressure of at least 250 psi, and recovering hydroconverted products fected under a hydrogen partial pressure of at least 800 psi.

therefrom. 4. The process of claim 1 wherein said organic materials 2. The process of claim 1 wherein hydroconversion is efcomprise coalf t d at atempcraturc f275 450 c 5. The process of claim 1 wherein said orgamc matenals 3. The process of claim 1 wherein hydroconversion is ef- 5 comprise peu'oleum derivedliquids- 

2. The process of claim 1 wherein hydroconversion is effected at a temperature of 275* -450* C.
 3. The process of claim 1 wherein hydroconversion is effected under a hydrogen partial pressure of at least 800 psi.
 4. The process of claim 1 wherein said organic materials comprise coal.
 5. The process of claim 1 wherein said organic materials comprise petroleum derived liquids. 